V link transmission belt



Jan. 31, 1961 RUNTQN 2,969,686

V LINK TRANSMISSION BELT Filed March 20, 1958 2 Sheets-Sheet 1 ZW J31cko/v Mung/V701? 554/5 A. PU/VTOA/ f l w 4 A TTOR/VEY I 31, 1961 RUNTQN2,969,686

V LINK TRANSMISSION BELT Filed March 20, 1958 A TTO/P/VEY 2 Sheets-Sheet2 United States Patent "ice v LINK TRANSMISSION BELT Leslie A. Runton,Middle Haddam, Conn., assiguor to The Russell Manufacturing Company,Middletown, Conn., a corporation of Connecticut Filed Mar. 20, 1958,Ser. No. 722,685

2 Claims. (Cl. 74-236) having improved stud means for securing theoverlapped links together.

A further object is to provide a belt of the above type which is highlyresistant to transverse compression in the pulley grooves.

A still further object is to provide a belt of the above type in whichthe links are formed at least on their exposed surfaces of a materialwhich is resistant to abrasion and has a low coeflicient of friction sothat the overlapped links can slide freely as the belt flexes to passaround the pulley.

Various other objects and advantages will be apparent as the nature ofthe invention is more fully disclosed.

In one embodiment of the invention each link is made from a multi-plyfabric in which at least one ply contains straight stiff fillers formingtransverse columns which are resistant to axial compression, and atleast one other ply includes straight continuous filament, high tensilefillers running longitudinally to impart a high resistance tolongitudinal stretching. Such longitudinal fillers are preferablycomposed of a material having a low coefficient of friction and areexposed at the surface of the link to impart such lom frictioncharacteristics thereto. Such a material may comprise a multifilamentyarn composed of a polymeric fluorocarbon resin such astetrafluoroethylene (Teflon). This material is characterized by hightensile strength and a high degree of dimensional stability, abrasionresistance and a very low coefiicient of friction.

Successive links are secured by studs extending loosely through theoverlapped links and having heads shaped to grip and clamp the fabricfor locking the links together when the studs are shifted into inclinedposition due to the tension of the belt.

The specific nature of the invention will be better understood from thefollowing description, taken in connection with the accompanyingdrawings in which a par ticular embodiment has been set forth forpurposes of illustration.

In the drawings:

Fig. 1 is a side elevation of a portion of a V link belt embodying theinvention;

Fig. 2 is a transverse section through a portion of a pulley showing apair of belts in driving position in pulley grooves;

Fig. 3 is a detail view of the fabric weave;

Fig. 4 is a longitudinal section through a portion of a belt embodyingthe invention illustrating the change in position of studs as the beltflexes around the pulley; and

Fig. 5 is a perspective view of a link from which the belt is formed.

2,969,686 Patented Jan. 31, 1961 Referring to the drawings more indetail, the belt is shown as composed of a plurality of links 10 whichoverlap and are secured together by studs 11. Each link 10, asillustrated in Fig. 5 is composed of a flat fabric strip having threeholes 12, 13 and 14 to receive successive studs 11.

The leading hole 12 (in the direction of belt travel) and the centerhole 13 are joined by a slit 15 having an enlarged opening 16 midway ofits length through which the stud may be passed for assembling the belt.One stud 11 is passed through this opening 16 and passed along the slit15 to the leading hole 12 and a second stud 1.1 is passed through theopening 16 and passed along the slit 15 to the center hole 13.

p The hole 14 at the trailing end of the link is provided with a shortslit 17 to facilitate the insertion of a stud11.

Before assembly a stud 11 is inserted in the hole 14 of each link and isthen passed through the openings 16 of the successive overlapped linksto build up the endless belt as illustrated in Figs. 1 and 4.

Each stud 11 is formed with heads 18 having under surfaces 19 which arein the form of a truncated cone the radii of which extend at apredetermined angle, for example, an angle of 38, with respect to anormal to the axis of the stud. The angle selected will be such thatwhen the studs 11 assume an inclined positiondue to the tension of thebelt as shown in Fig. 4 the surfaces 19 of the heads 18 extend parallelto the surface of the links and tend to exert a compressive force on.the fabric for securing the overlapped links together. The angle of tiltof the studs will depend upon the compressibility of the fabric and thelength of the studs with respect to the thickness of the links. Whenthecompression of the fabric by the links balances the force exerted bythe heads 18 of the studs due to the pull of the belt no furtherdisplacement can take place.

It will be noted that the studs 11 are free to shift in position toaccommodate the variation in overlap of the inner and outer links as thebelt flexes to pass around a pulley 20 as seen in Fig. 4. The tilt ofthe studs 11 becomes less as the belt flexes. However, because the heads18 are not fixed to a link, the change in tilt does not cause theadjacent part of the link to bend nor does the head rub on the fabric tocause wear.

Fig. 2 shows the relative position of a pair of such belts in V grooves21 of a pulley 20 where the driving force is due to the grip of theinclined sides 22 of the pulley which define the grooves 21.

Each link 10 is made from a molded and heat curled resin-impregnatedfabric composed of a plurality of woven plies 30 consisting of straight,stiff, compression resistant fillers 31 of heat-set nylon or Dacronmonofilament or of other synthetic resins of large denier woven withthin flexible chain warps 32 of a material such as cotton, spun Dacronor spun Orlon which is bondable to the impregnant. The plies 30 form theinner ply or plies of the fabric.

Outer plies 35 are composed of straight continuous filament fillers 35of high tensile, heat-set material such as Teflon or Dacron woven withflexible chain warps 37 of bondable material similar to the warps 32.When the fillers 36 are composed of a polymeric fluorocarbon resin suchas Teflon which is not bondable to the bonding resin the chain warps 37may be composed of cotton or other material which is readily bondable tothe bonding resin and which serves to hold the nonbondable filler yarnsin place to constitute the exposed surface of the link.

The woven plies are impregnated with an elastomeric resin formingimpregnant such as a rubber latex or polyvinyl chloride and dried andheat cured to a degree to stabilize the fillers. The plies are thensuperimposed with the fillers 31 running transversely and the fillers 36running longitudinally to build the fabric up to the desired thicknessand vulcanized or cured under heat and pressure to form a multi-plyfabric in which the various plies are bonded together by the impregnant.The links are cut from this fabric.

The number of inner plies 30 depends upon the desired transversecompression resistance of the links. The number of outer plies may alsobe varied and in the case of a plurality of such plies the filler yarns36 of all except the surface ply may be composed of Dacron or othermaterial which is readily bondable, the filler yarns 36 of the outerplies only being composed of Teflon.

The various rows of fillers 31 form transverse columns which are highlyresistant to axial crushing and impart compression resistance to thelinks.

The outer plies 3S impart longitudinal stretch resist-' ance to thelinks 10. 7 I Since the stiif fillers 31 run transversely only and thechains 32 of the plies 30 and the fillers 36 of the plies 35 which runlongitudinally are flexible, the links readily flex to pass around thepulleys but retain their transverse stability to an extent to resistdistortion in'the pulley grooves. The low friction surface of the linksreduces Wear and thereby increases the useful life of the belt as wellas its ability to flex readily about pulleys of small radius.

Although a specific embodiment has been described for purposes ofillustration the invention may be adapted to various uses and variousembodiments will be apparent to a person skilled in the art.

What is claimed is:

1. A V link belt comprising a plurality of links secured together inoverlapping relationship, each link being composed of a multi-ply fabrichaving inner and outer plies impregnated with an elastomeric moldedresin, said inner plies being composed of straight stifi monofilarnentfillers composed of a synthetic resin forming transverse columnsresistant to axial compression and flexible chain warps woven with saidfillers to bind the latter in place, said outer plies being composed oflongitudinally extending continuous filament filler yarns woven withflexible chain yarns of a material which is readily bondable to saidresin.

2. A V link belt comprising a plurality of links secured togetherinoverlapping relationship, each link being composed of a multi-ply fabrichaving inner and outer plies impregnated with an elastomeric moldedresin, said inner plies being composed of straight stifl monofilamentfillers composed of a synthetic resin forming transverse columnsresistant to axial compression and flexible chain warps woven with saidfillers to bind the latter in place, said outer plies being composed oflongitudinally extending continuous filament filler yarns composed oftetrafluoroethylene woven with flexible chain yarns of a material whichis readily bondable to said resin, said last filler yarns being exposedto provide a surface having low friction characteristics. I

References Cited in the file of this patent UNITED STATES PATENTS2,135,057 Slayter et al. Nov. 1, 1938 2,189,049 Ungar Feb. 6, 19402,444,903 Van Buren July 6, 1948 2,684,315 Spicer -1 July 20, 19542,773,781 Rodman Dec. 11, 1956 2,792,319 Fihe May 14, 1957 2,840,881Bateman July 1, 1958 2,848,901 Groff Aug. 26, 1958 FOREIGN PATENTS741,708 Germany Nov. 15, 1943

